Sir John Blackwood, 2nd Baronet (1721 – 27 February 1799) was an Irish politician and baronet. He was the eldest son of Sir Robert Blackwood, 1st Baronet of Ballyleidy Blackwood entered the Irish House of Commons for Killyleagh in 1761 and sat for it until 1768. He was then returned for Bangor until 1776. He was member of parliament for Killyleagh again until 1790 and subsequently for Bangor until 1798. From the latter year to his death in 1799, he represented Killyleagh a third time.